DESCRIPTION (Based on Applicant Abstract): The focus of this application is on brain "aerobic glycosis", a term applied to the disproportionately greater increase in glucose than oxygen utilization in working brain. The general hypothesis to be tested is that glucose taken up in excess of oxygen is used to restore metabolic pools depleted at the onset of stimulation, rather than to generate lactate. Dr. Dienel proposes to develop a rat model of aerobic glycosis using generalized sensory stimulation, then assay changes in brain levels of major metabolites and flux of radiolabelled glucose into major pathways, some specific to neurons (GABA) or glia (glycogen and glutamine), using biochemical, autoradiographic, and microdialysis techniques. To determine the cellular basis of metabolism during aerobic glycosis, Dr. Dienel will use radiolabelled "glial reporter molecules" (butyrate, acetate) and autoradiography to examine glial contributions.